{ "id": "2402.10719", "version": "v1", "published": "2024-02-16T14:20:58.000Z", "updated": "2024-02-16T14:20:58.000Z", "title": "A current based approach for the uniqueness of the continuity equation", "authors": [ "Tommaso Cortopassi" ], "comment": "13 pages", "categories": [ "math.AP" ], "abstract": "We consider the problem of proving uniqueness of the solution of the continuity equation with a vector field $u \\in [L^1 (0,T; W^{1,p}(\\mathbb{T}^d)) \\cap L^\\infty ((0,T) \\times \\mathbb{T}^d)]^d$ with $\\operatorname{div}(u) ^- \\in L^1 (0,T; L^\\infty (\\mathbb{T}^d))$ and an initial datum $\\rho_0 \\in L^q (\\mathbb{T}^d)$, where $\\mathbb{T}^d$ is the $d$-dimensional torus and $ 1 \\leq p,q \\leq +\\infty$ such that $1/p + 1/q =1$ without using the theory of renormalized solutions. We propose a more geometric approach which will however still rely on a strong $L^1$ estimate on the commutator (which is the key technical tool when using renormalized solutions, too), but other than that will be based on the theory of currents.", "revisions": [ { "version": "v1", "updated": "2024-02-16T14:20:58.000Z" } ], "analyses": { "subjects": [ "35F10", "35L03", "49Q15" ], "keywords": [ "continuity equation", "renormalized solutions", "geometric approach", "vector field", "dimensional torus" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }